A woman's body scrawled with religious texts is found in a Helsinki apartment. Jewish homicide inspector Ariel Kafka investigates. What begins as an investigation of Christian religious lunatics shifts into a hunt for a perpetrator who is more damaged than dangerous, the victim of institutionally countenanced paedophilia at a boarding school. Ariel Kafka finds himself investigating a series of crimes leading to the enigmatic Brotherhood of the Sacred Vault, founded at the school. The brotherhood's former members have gone on to become Oxford professors and important CEOs, all reluctant to recall their school days. But before Kafka can solve the puzzle, more than one person must pay for past sins with his life. The final twist takes the investigation in a different direction - the ultimate motivation for the crimes is money, with the mentally unstable alleged perpetrator being used as bait.